Psychiatry and the brain

Psychiatry and the brain

By George Graham and Owen Flanagan

Even before the much-heralded DSM-5 was released, Thomas Insel the Director of NIMH criticized it for lacking “scientific validity.” In his blog post entitled “Transforming Diagnosis,” Insel admitted that the symptom-based approach of DSM is as good as we can get at present and that it yields “reliability” by disciplining the use of diagnostic terminology among professionals. But (he went on) DSM-5 does not reveal the nature of a mental disorder, which is to be found largely in the head. In an interview with the New York Times, Insel said “his goal was to reshape the direction of psychiatric research to focus on biology, genetics and neuroscience so that scientists can define disorders by their causes, rather than their symptoms.” At the same time, Insel has announced a new initiative called Research Domain Criteria Project (RDoC) at NIMH to develop a new nosology that eventually will replace DSM categories. He writes that this program began with a number of assumptions, two of which are:

“A diagnostic approach based on the biology as well as the symptoms must not be constrained by the current DSM categories.”

Insel sells RDoC as a replacement of DSM on grounds that “patients with mental disorders deserve better.”

No doubt, patients deserve the best. But is RDoC really the direction in which psychiatry and mental health medicine ought to go? Does a nosology that explicitly pre-privileges the brain and genetics and that begins with the assumption that mental disorders are brain disorders start from a reasonable assumption? Or is this more likely an empirically contentious, discipline non-neutral position about the nature of mental disorders?

Sometimes scientists believe that mental disorders are based in the brain. They don’t recognize that just because a disorder necessarily involves the brain doesn’t mean that it is of the brain (viz. a brain disorder). Consider: One of the reinforcement schedules that is responsible for much human and non-human animal learning is the so-called variable ratio schedule of reinforcement, in which reinforcement is delivered occasionally and unpredictably. It is a powerful schedule for the acquisition of new behavior and well-suited for creatures like us who often must persist in trying to satisfy needs in the face of possibilities of protracted failure. However, when pursued in certain environments, the schedule can lead to gambling addictions and to other patterns of imprudence that qualify as disorders. The brain contains a capacity to squander a family’s resources on a final trifecta.

To get a gambling addict to disengage from a harmful schedule of reinforcement at race tracks or casinos you don’t need to fix the brain. It is not broken. It is behaving as it should from a biological point of view. Indeed, to redesign the brain so that it makes gambling addictions impossible would be a huge mistake.

Our proposal is this: In any particular case of mental illness, even a kind or type of mental illness, the brain may not be at fault. As a brain, it may be in perfectly good working order.

To be sure, we all wish for superior psychiatric diagnostic labels for mental illnesses and for the explanation of the onset and course of illness. Certainly none of us wishes to strip reference to the brain and biological science of an important role in our understanding of mental illness. We need help from brain science for much that we want to know about a disorder. But we need other disciplines as well.

The best picture of a mental illness is not likely to be found in a single, precise, biologically privileged ‘frame’ (viz. a biological marker). The best picture is more likely to be found in the overall manner of organizing the most useful perspectives about an illness that we have or otherwise achieve. Perspectival multiplicity, when properly channeled and evidentially controlled, is often not just the best but the only way in which to understand a phenomenon. Imagine, for example, trying to understand a soccer or tennis match just by deploying the physics of space, time, and motion. It just cannot be done. We need references to human psychology, history, and cultural context.

Ironically, despite his impatience with DSM-5, both DSM-5 and Insel’s aspirational RDoC share one methodological prejudice in common. Both disfavor etiology or history and context in defining mental disorders. In DSM’s case, present symptom clusters are placeholders for eventual filling in by something like RDoC’s neurobiological markers supplemented perhaps by genetic markers. In both DSM and RDoC, mental disorders are conceived exclusively in synchronic or present-tense terms, notdiachronically as complex social-emotional-behavioral syndromes with complex histories and long backtracking arms.

To see where and why non-brain science is important to our understanding of mental illness, we need to assemble a number of points that cannot be assembled here. Mental illness will not be understood by those who live in disconnected sets of scientific rooms or aspire to a single pre-determined resting place of theory.

George Graham is the co-editor of The Oxford Handbook of Philosophy and Psychiatry with KWM Fulford, Martin Davies, Richard Gipps, John Sadler, Giovanni Stanghellini, and Tim Thornton. He is a former president of the Society for Philosophy and Psychiatry, and teaches philosophy at Georgia State, having taught at Alabama-Birmingham and Wake Forest. Owen Flanagan is also a former president of the Society for Philosophy and Psychiatry, and teaches philosophy at Duke, having taught at Wellesley.